Similar outcomes between adenoid cystic carcinoma of the breast and invasive ductal carcinoma: a population-based study from the SEER 18 database

Abstract

Adenoid cystic carcinoma of the breast (breast-ACC) is a rare and indolent tumor with a good prognosis despite its triple-negative status. However, we observed different outcomes in the present study. Utilizing the Surveillance, Epidemiology, and End Results (SEER) database, we enrolled a total of 89,937 eligible patients with an estimated 86 breast-ACC cases and 89,851 invasive ductal carcinoma (IDC) patients. In our study, breast-ACC among women presented with a higher proportion of triple-negative breast cancer (TNBC), which was more likely to feature well-differentiated tumors, rare regional lymph node involvement and greater application of breast-conserving surgery (BCS). Kaplan-Meier analysis revealed that patients with breast-ACC and breast-IDC patients had similar breast cancer-specific survival (BCSS) and overall survival (OS). Moreover, using the propensity score matching method, no significant difference in survival was observed in matched pairs of breast-ACC and breast-IDC patients. Additionally, BCSS and OS did not differ significantly between TNBC-ACC and TNBC-IDC after matching patients for age, tumor size, and nodal status. Further subgroup analysis of molecular subtype indicated improved survival in breast-ACC patients with hormone receptor-positive and human epidermal growth factor receptor 2-negative (HR+/Her2-) tumors compared to IDC patients with HR+/Her2- tumors. However, the survival of ACC-TNBC and IDC-TNBC patients was similar. In conclusion, ACCs have an indolent clinical course and result in similar outcomes compared to IDC. Understanding these clinical characteristics and outcomes will endow doctors with evidence to provide the same intensive treatment for ACC-TNBC as for IDC-TNBC and lead to more individualized and tailored therapies for breast-ACC patients.

Histologic subtyping affecting outcome of triple negative breast cancer: a large Sardinian population-based analysis

“…Furthermore, five case reports on patients with breast adenoid cystic carcinoma showing one or more distant metastasis have been published [51]. Chen et al using a large number of population-base data showed that breast adenoid cystic carcinoma has different pathological features and good clinical course compared to IBC-NST, but comparing BC Triple Negative phenotype no differences were shown between the two histologic types as far as recurrence and mortality are concerned [52]. Patients with adenoid cystic carcinoma exhibited smaller size and limited distribution of tumor size than patients with IBC-NST (p = 0.050), according to the results of Mills et al [12].…”

Triple-negative breast carcinomas of low malignant potential: review on diagnostic criteria and differential diagnoses

“…C-AdCC usually carries a good prognosis, despite the triple-negative phenotype. Almost all studies but one [28] demonstrated that C-AdCC recurrences or progression to metastases are exceedingly rare. Nevertheless, care should be taken to radically excise AdCC.…”

Adenoid cystic carcinoma of the breast – an uncommon malignancy with unpredictable clinical behaviour. A case series of three patients

“…AdCC affects mainly Caucasian women of age ranging from 33 to 97 years (mean age of 64) [ 3 ]. About 50% of tumours are found in a periareolar region and are well-circumscribed, palpable, tender masses, often associated with pain and nipple retraction [ 4 ]. It is typically a slow-growing lesion without the involvement of locoregional lymph nodes (in less than 2% of cases) or presence of distant metastases [ 4 ].…”